The invention is aimed in particular, although not exclusively, at hydraulic manipulators designed as mentioned above.
FIG. 1 of the appended drawings illustrates a known arrangement of a manually-operated remote-control device, in this case, more specifically a hydraulic manipulator. The device essentially comprises:
a body 1 containing at least one (and in practice from one to four) moving member that generates a signal (a pressure reducer in the example of the hydraulic manipulator)--which is not visible in the drawing--when moved, especially linearly parallel to the axis of the body, between two extreme positions, PA1 a push-rod 2 associated with each generating member and projecting beyond the top of the body 1, this push-rod being engaged in a guide 3 supported by the body so as to be able to move substantially axially, PA1 a rocking cam 4 fixed to the top of the body and able to interact with the projecting end of the push-rod(s) to control the movement thereof when it is tilted; PA1 means 5 of articulation in tilting which are inserted between the top of the body and the cam 4, comprising a fixed clevis mount 5a secured to the body 1 (for example, the clevis mount 5a is fitted with a threaded stem 11 which is screwed into the body 1, passing through a hole 12 made in a top plate or attachment plate 13 that closes the body: the clevis mount 5a, screwed into the body 1, then also acts as means of attaching the plate 12 to the body 1) and a moving clevis mounts 5b secured to the cam, the said clevis mounts 5a, 5b being coupled together in such a way as to allow the cam 4 to rock with respect to the body; in practice, when there is one push-rod or two diametrically opposed push-rods, the clevis mounts 5a, 5b are articulated together by a simple pivot pin transverse to the axis of diametral alignment of the push-rods; when there are two, three or four push-rods arranged on two approximately orthogonal axes, the clevis mounts 5a, 5b are articulated together by a member for multi-directional inclination of the cam, such as a ball-joint or a cardan joint as schematically illustrated more particularly in FIG. 1; PA1 a base 6 surmounting the cam 4 and secured thereto; and PA1 a handgrip 7 comprising a grip part 7a and a rod 7b for mounting in the base 6.
In this particular embodiment, the articulation means 5, and in particular the moving clevis mount 5b, the cam 4 and the base 6 are constructed in the form of three independent components, machined separately, even made of different materials, and assembled together essentially by screwing: the base 6 is pierced axially at 8 and threaded internally; the cam 4 has a central recess at 9; the moving clevis mount 5b has a threaded rod 10; the cam 4 is slipped over the threaded rod 10 and locked on the moving clevis mount 5b by the base 6 which is screwed onto the threaded rod 10, and which thus forms the lock nut for the cam; then the rod 7b of the handgrip 7, which is threaded at its free end, is screwed into the base 6.
The result of this is that manufacturing the constituent components of the push-rod controls individually requires a great many and expensive machining operations, followed by an assembly operation which takes time and is therefore costly.